NEW YORK — Coming just weeks after the explosion of global anti-Semitism that followed Israel’s military action in Gaza, the timing couldn’t have been better for the London Conference on Combating Anti-Semitism, held Feb. 16 and 17.

With Jewish communities around the world feeling insecure and vulnerable, with synagogues vandalized and an atmosphere of intimidation and fear permeating anti-Israel rallies, there was a sense that even though this conference had been months in the making, it was a propitious moment for deliberation and action.

Having just returned from the London meeting, where I chaired a working group on fighting anti-Semitism in the political sphere, I can say that there is at least a sliver of hope that these challenges can be met, that there is a willingness and a commitment by some in the international community who are ready to stand up and say “no” to anti-Semitism, and to put up a united front against bigotry and hatred.

More than 120 lawmakers from more than 40 nations spanning the globe came together to devise an effective framework and forge new strategies to confront anti-Semitism on a global scale.

This is the good news in an otherwise bleak picture, one that I fear is only going to get bleaker as world Diaspora Jewry faces this new threat.

Although the conference was planned months ago to deal with the growing and increasingly sophisticated manifestations of global anti-Semitism, it clearly took on much greater significance as a result of the pandemic of anti-Semitism that erupted during Israel’s Gaza offensive. As it happens, the Gaza reaction became the main focus of our discussions.

Let’s take a moment to revisit what happened in the weeks after Israel launched the Gaza offensive on Dec. 27.

It was as if the floodgates had been opened. Within days an open season had been declared on world Jewry. It started with criticism of Israel: Israel was wrong. Israel was evil. Israel was satanic and a violator of international human rights and international law. This theme quickly morphed into talk about war crimes and war tribunals.

In cities around the world, rhetoric at rallies and demonstrations against Israel reached a fever pitch with the most outrageous language imaginable and comparisons of Israelis and all Jews to Nazis, to Hitler, to swastikas. The language was unmistakable and ubiquitous — the Star of David equals the swastika, the accusation that Gaza is the same as Auschwitz, the victims of the Holocaust are now the perpetrators of a new one. The shouts of “Jews to the Gas” — shamelessly shouted in public, even in Fort Lauderdale, Fla. — spread quickly across the Internet along with much worse expressions of hatred for Israel and Jews.

Jewish communities felt pressure as never before. In Venezuela, the community of nearly 15,000 woke up to a nightmare of anti-Semitic expression aided and encouraged by President Hugo Chavez and his government, who expelled the Israeli ambassador and called on Jewish Venezuelans to renounce their allegiance to Israel. In Caracas, a synagogue was vandalized in an orgy of anti-Semitism: the Torah scrolls thrown to the floor, the walls daubed with anti-Jewish epithets and threats, the membership rolls stolen. The Venezuelan media and Web sites were filled with expressions of hatred for Israel and calls for Jews to be expelled from the country.

Venezuela was not an isolated case. Reports flooded in from Jewish communities around the world that were feeling similar pressures. European countries, including democratic, Western nations such as France, Belgium and Great Britain, witnessed an outpouring of hatred aimed at Jews. The hateful rhetoric at rallies often was followed by violence, sometimes by demonstrators, other times by unidentified perpetrators who aimed Molotov cocktails at synagogues and other visibly Jewish institutions and property.

This is why the word “pandemic” applies to what we are witnessing. Not only has it spread more widely than we have ever witnessed — even during the second intifada, when Israel faced suicide bombings in the heart of Jerusalem, it was not this intense — but it has metastasized with accusations of dual loyalty and Holocaust denial thrown into the mix.

This is the worst, the most intense, the most global hatred aimed at Jews in most of our memories. When was the last time we can remember Jews being beaten in the street, as happened in the United Kingdom, where 220 incidents were reported during the three weeks of Israel’s military operation, an eight-fold increase compared to the same period a year ago?

Likewise, in Amsterdam, Antwerp, Athens, Barcelona, Berlin, Caracas, Florence, Montevideo and Paris, Jews have been beaten on the street, synagogues have been firebombed and desecrated, and Jewish institutions, businesses and homes have been attacked.

And for what reason? Because Israel, a sovereign nation, sought to defend itself from the constant barrage of Hamas missiles threatening its cities.

Today, the sense of urgency has never been greater. We are fortunate to have a commitment from some leaders, those who gathered in London and others who have taken the time to understand the nature of the threat. From this I hope will come government action to put a damper on anti-Semitism.

(Abraham H. Foxman is national director of the Anti-Defamation League and author of “The Deadliest Lies: The Israel Lobby and the Myth of Jewish Control.”)